A rapid prototyping technology (also called Rapid Prototyping Manufacturing, RPM), also known as 3D printing, is a high-tech manufacturing technology based on a material accumulation method. This technology can manufacture an entity or an entity model through the shaping equipment adopting the material accumulation method, according to three-dimensional model data of the parts or the object. With the advantages of significant reduction in production costs, utilization improvement in raw material and energy, customization according to demands, significant saving in product production time, etc., the 3D printing technology gradually comes into public view and gets a rapid development in recent years.
The basic principle of the 3D printing is: processing layer by layer, and shaping by stacking, that is, generating the 3D entity by stacking material layer by layer. In the 3D printing process, firstly the 3D model of the object to be printed is obtained by manners of designing, scanning, etc. through a computer, and then a series of digital slices are completed along a certain direction by a computer aided design technology (such as CAD), and then the information of these slices are transferred to a 3D printer, a computer generates a machine instruction based on the slices, and the 3D printer prints a thin layer based on the machine instruction, continuous thin layers are stacked until a solid object is shaped, forming a three-dimensional entity, and then the 3D printing is completed.